This invention relates to a structure such as a spacecraft, and, more particularly, to a construction that achieves electrostatic charge dissipation at the surface of the structure.
Flight vehicles such as spacecraft develop electrostatic surface charges due to a variety of causes. When the outer skin panels are made of metals, that charge is readily conducted away and dissipated. However, when the outer skin is made of a nonconductive nonmetallic material or is coated with a nonconductive nonmetallic coating, the electrostatic charge is not mobile and may locally build up to high levels that can damage sensitive electronic equipment or the occupants of the vehicle, or can interfere with communications.
To dissipate the electrostatic charge in the latter instance, the outer skin panels may be coated with thermal control coatings which are also sufficiently electrically conductive to conduct the electrostatic charges away for dissipation. If the outer skin is made of multiple panels, the panels are bonded with a structural adhesive and interconnected with electrical conductors such as tabs or straps to allow the electrostatic charges to flow between panels, and eventually to dissipate. The tabs or straps are bonded to the panels with a silver-filled, non-structural adhesive, which is overcoated with a clear dielectric organic coating to prevent silver particles from contaminating the vehicle. This process is time consuming and expensive.
There is a need for an improved approach to the control of electrostatic-charge accumulation on flight vehicles. The present invention fulfills this need, and further provides related advantages.